Take a vacation. Really.

Other businesses are sending similar messages. This month PricewaterhouseCoopers, a professional-services firm, kicked off a 10th-anniversary celebration with a day called "Take Your 10," urging employees to take their 10 paid holidays, as well as vacation. To emphasize the importance of time away, the firm distributed a booklet, "Rest and Relaxation: The Value of Time Off," to all 30,000 employees. The company's website also offers suggestions about how to use that time. Vacation has even become an issue on performance reviews.

"Managers would receive reports about members of their team who had stopped earning vacation because they had reached their cap," says Michael Fenlon, managing director of people strategy. "We wanted to change that and build a culture in which uninterrupted work-free vacations were more the norm than the exception."

For several years, Scott Stevenson, director of advisory practice at Pricewaterhouse­Coopers, did not take all of his vacation days. "There was almost a feeling of guilt when you took time off," he says.

Now Mr. Stevenson uses almost all of his allotted four weeks, some of it in half-day increments. Although he concedes that he still has "a twinge of guilt sometimes," he says, "I do credit the firm for having us talk about it more, and the need for it, and the value of it to the work we do."

Although staffing is tight at TripAdvisor, a website in Newton, Mass., the company encourages all employees to take their vacation. It even added four summer Fridays to everyone's holiday schedule. "The bosses are leading by example, promising to take them all," says spokesman Brian Payea. "Everyone gets a minimum of three weeks' vacation at the start, plus the new summer Fridays."